Anti-TPO : what is this test and what is it for?

 An anti-TPO test, also known as a thyroid peroxidase test, measures the level of antithyroid microsomal antibodies in your blood

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. Thyroperoxidase is an enzyme involved in thyroid hormone synthesis, and the microsomal antibody test helps monitor autoimmune thyroid diseases and helps analyze the particular specimen or form of thyroiditis

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Indications and Preparation

If you've been diagnosed with thyroid disease, your doctor may suggest a TPO antibody test and other thyroid tests to help find the cause

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. You do not need to fast for the anti-TPO test, but be sure to inform your doctor of any medication, drugs, or herbal supplements you may be taking before you go in for the test

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Standard for Anti-TPO Antibodies

The 1st International Standard for anti-thyroid peroxidase antibodies, coded 19/260, is intended for use in the calibration of immunoassays for anti-thyroid peroxidase

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. It replaces the NIBSC Reference Reagent (NRR), coded 66/387, for anti-thyroid microsome serum, which was produced in the 1960s as a research reagent for anti-thyroid microsome activity

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Interpretation of Test Results

The presence of TPO antibodies in your blood suggests that the cause of thyroid disease is an autoimmune disorder, such as Hashimoto's disease or Graves' disease

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. In autoimmune disorders, your immune system makes antibodies that mistakenly attack normal tissue. Antibodies that attack the thyroid gland cause swelling, rarely tenderness, and reduced function of the thyroid

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. A normal range of TPO-Ab (+) was defined as below 16 IU/mL

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.It is important to note that if you are on certain medications, the test results could be false positive or negative

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References

1. https://www.portea.com/labs/diagnostic-tests/microsomal-tpo-antibody-80/
2. https://www.nibsc.org/documents/ifu/19-260.pdf
3. https://www.mayoclinic.org/thyroid-disease/expert-answers/faq-20058114
4. https://endocrinology.testcatalog.org/show/TPO
5. https://www.btf-thyroid.org/thyroid-antibodies-explained
6. https://www.myupchar.com/en/test/anti-tpo-thyroid-peroxidase-antibody
7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7505314/

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portea

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mayoclinic

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nibsc

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nih